Knitting machine



March 20, 1945. s; SAFTLAS 2,372,019

KNITTING MACHINE Filed March 11, 1944 IN'VENTOR JAM/a div/7M0 ATTORNEYS Patented Mar. 20, 1945 UNITED STATES PATENT OFFICE KNITTING MACHINE Samuel Saftlas, West Warren, Mass.

Application March 11, 1944, Serial No. 526,009

(Cl. 66-l) 1.0 Claims.

. This invention relates to improvements in knitting machines and more particularly to means for preventing the production of imperfect fabric when the machines are started up after a period of disuse.

The normal running temperature of the operating parts of a knitting machine is relatively high due to the friction of the rapidly moving parts, and the parts are designed for normal operation at such temperature. When for any reason the machines are stopped for a substantial period, the parts cool resulting in contrac* tion of the metal and stiffening of the lubricants. When the machines are restarted, the movement of the parts takes place under conditions of strain which causes variable tensions on the yarns or threads with the result that the fabric produced is defective until the machines warm up to at least an approximation of normal operating temperatures. Since for practical purposes the machines, during usual stoppages such as at night, must be left threaded and unfinished labric left on the machines, a substantial loss of material results. This loss is particularly large in cold weather.

It is the principal object of my invention to overcomethis difliculty and to avoid the loss from imperfect fabric due to the low starting temperature of the machine.

More power is required to start a cold machine than is needed for the operation of the same machine when at operating temperature. My invention therefore makes it possible to use lower powered motors, in the case of individual motor driven machines, and in the case of machines driven from a common motor it makes possible some saving in current.

I have found that the principal operational difficulties center around the cylinders, beds and sinker dials, and the parts associated therewith such as the adjacent sinkers and needles and the various actuating cams and levers. According to my invention, I incorporate in the machine one or more electrical heating elements so positioned and controlled that the critical parts may be maintained at the minimum operating temperature or may be quickly brought to that temperature before the machines are restarted.

The needle cylinder or bed represent relatively large masses of metal closely associated with the critical parts and for most conditions I have found that a single heating member inserted in the wall of the needle cylinder or bed, or positioned closely adjacent that face of the cylinder or bed opposite that on which the needles operate is eifective for my purposes. In the type of machine using a needle or sinker dial the dial may be similarly supplied with a heating unit if found necessary or desirable.

In the accompanying drawing, which diagrammatically shows illustrative embodiment of my invention,

Fig. 1 is a plan view of the needle cylinder of a knitting machine, of the stationary cylinder type, parts being broken away, embodying my invention;

Fig. 2 is a section substantially on line 22 of Fig. 1;

Fig. 3 is a fragmentary sectional view showing one manner of applying the invention to a rotary cylinder type of machine;

Fig. 4 is a sectional view of a rotary needle dial in which the invention is incorporated, and

Fig. 5 is a fragmentary sectional view showing the invention applied to a double bed machine.

Referring to the drawing, l0 designates the needle cylinder of a knitting machine. The outer surface of the cylinder is provided in the usual manner with a multiplicity of grooves in which the needles, one of which is shown at I2 are reciprocated by conventional mechanism, not shown. Figs. 1 and 2 illustrate a fixed cylinder type of machine and as shown in Fig. 2 the cylinder is secured, as by machine screws 13, to a ring member M secured in any suitable manner to the machine table l5. As will be understood the fabric from the needles passes downwardly through the center of the cylinder over a shield l6 secured to the inner edge of the ring I4 in any suitable manner as b bolt ll. The upper edge of shield l6 is flared as at l8 to bring said edge into close proximity to the cylinder.

Between the shield l6 and the inner surface of the cylinder is secured a heating coil 19. The coil may be of any suitable form. Preferably it is placed closely adjacent the inner face of the cylinder and is supported on a core 20 which is formed of a material having a relatively low heat conductivity in order both that the heat from the coil may be concentrated on the cylinder and that the shield 16, which is in contact with the finished portion of the fabric, will not be excessively heated.

The coil is supplied with current from any suitable source through leads 2l. The current supply may be automatically controlled by a suitable rheostat or current regulator under the control of a suitable timer or thermostatically operated switch as diagrammatically indicated at 22. The specific form of the control devices used will of grooves t l course depend on the operating conditions of the factory in which the machines are installed. For example, a timer operating for a longer or shorter period in response to the prevailing temperature will in most cases be satisfactory.

In Fig. 3 is illustrated a rotary cylinder type of machine in which the ring [4, to which the cylinder in is secured, is rotatably mounted in the table 15. In the form illustrated, the cylinder is driven through a ring gear 23, formed on the lower face'of ring M, and meshing with a gear 24 secured to a drive shaft 25. Current may be supplied to the coil l9 throughwires 26 connected to rings 2'! supported by an insulating ring 28 secured to the upper face of ring l4. Current is supplied to the rings 21 by stationary brushes 29.

In some forms of both stationary and rotary cylinder machines a sinker or needle dial either annular disc shaped is used at the top of the cylinder and it is desirable to apply a separate heating coil to the under face of the dial. One form of such application. is illustrated in Fig. 4 which shows a needle dial. As shown, the under face of the dial 30 is recessed at 3| to receive the heating coil 32. A shield plate 33 protects the finished fabric below from excessive heating. The plate 33 is secured in place by machine screws 34 or other suitable means. The coil 32 maybe supplied with current through wires 35 extending upwardly through the shaft 36 which supports the dial. In case the dial is of the rotating type, the wires 35 may be supplied with current through rings 31 carried by the shaft and stationary brushes 38.

In Fig. 5 is shown the upper portion of the beds 49 of a double bed type of knitting machine, the outer surfaces being formed with the usual needle On the under side of the bedsare mounted heating coils 42 held in place by shields 43 secured to the beds by screws 44. The beds being stationary, current may be supplied directly to the coils by leads not shown.

The general heating of the machine is achieved by the direct radiation, of the heat from the coil, the conductivity of the metal parts, and the radiations therefrom, and by the circulation of the heated air. The efficiency of the latter factor may be increased by providing circulation openings such as openings and 45 through the, shield" and cylinder walls respectively as indicated in Fig.2.

While I have shown the preferred location of the heating coils for the structures illustrated it will be understood that the particular location of the coils will vary with the structure and design 1. In a knitting machine, means for decreasing imperfections in the fabric produced thereby during the initial period of operation of said machine which comprises an electric heating element and means to support said element in a fixed, heat transferring relation with the knitting instrumentalities of the machine.

2. In a knitting machine, means for decreasing imperfections in the fabric produced thereby during the initial period of operation of said machine which comprises an electric heating element and means to support said element in heat transferring relation with needle guiding element of the knitting machine.

3. In a knitting machine, means for decreasing imperfections in the fabric produced thereby during the initial period of operation of said machine which comprises an electric heating element and means to support said element in a fixed position adjacent the rear face of the needle guiding element of the knitting machine.

4. In a knitting machine, means for decreasing imperfections in the fabric produced thereby during the initial period of operation of said machine which comprises an electric heating element and means to support said element adjacent the inner surface of the needle cylinder of the machine.

5. In a knitting machine, means for decreasing imperfections in the fabric produced thereby during the initial period of operation of said machine which comprises a heating element disposed around a circumference of the knitting cylinder to bring the instrumentalities of said machine to operating temperature, said element being supported in a predetermined heat transferring relationship with said cylinder and instrumentalities.

6. In a knitting machine, means for decreasin imperfections in the fabric produced thereby dur ing the initial period of operation of said machine which comprises an electric heating element, means to support said element in fixed relation relative to the inner surface of the needle cylinder of the machine and means to shield the fabric on the machine from the direct heat of said element.

7. In a knitting machine, means for decreasin imperfections in the fabric produced there byduring theinitial period gfoperating'bf said machine which comprises'an electric heating element and means to support said element in fixed heat transferring relation with the body of metal with which the knitting instrumentalities are in heat conductive contact.

8. In a knitting machine a needle cylinder provided on its inner surface with an electric heating element.

9. In a knitting machine a needle bed provided on its under surface with an electric heating element. l

10. In a knitting machine a dial for supporting sinkers or needles and provided on its under side with an electric heating element.

SAMUEL SAFI'LAS. 

